Table1. Characteristics of the study subjects (N=283)
Quality of sleep
Variable n (%) Good n (%) Poor n (%) p value
Age (years) (59±7.3) 0.020#
<65 227 (80.2) 161 (70.9) 66 (29.1)
65~74 45 (15.9) 38 (54.4) 7 (15.6)
³75 11 (3.9) 5 (45.5) 6 (54.5)
Sex 0.317
Male 60 (21.2) 47 (78.3) 13 (21.7)
Female 223 (78.8) 157 (71.2) 66 (22.6)
Religious beliefs 0.513
No 61 (21.6) 46 (75.4) 15 (24.6)
Yes 222 (78.4) 158 (71.2) 64 (28.8)
Smoking history 0.284
No 268 (94.7) 195 (72.8) 73 (27.2)
Yes 15 (5.3) 9 (60.0) 6 (40.0)
Alcohol consumption 0.048
No 232 (82.0) 162 (69.8) 70 (30.2)
At least once a week 51 (18.0) 42 (82.4) 9 (17.6)
Tea consumption 0.407
No 116 (41.0) 85 (73.3) 31 (26.7)
At least once a week 167 (59.0) 119 (72.3) 48 (28.7)
Coffee consumption 0.521
No 110 (38.9) 79 (71.8) 31 (28.2)
At least once a week 173 (61.1) 125 (72.3) 48 (27.7)
Regular exercise 0.526
No 143 (50.5) 101 (70.6) 42 (29.4)
Yes 140 (49.5) 103 (73.6) 37 (26.4)
Chronic disease a 0.025
No 121 (42.8) 95 (78.5) 26 (21.5)
Yes 162 (57.2) 109 (67.3) 53 (32.7)
Heart disease 0.017
No 250 (88.3) 186 (74.4) 64 (25.6)
Yes 33 (11.7) 18 (54.5) 15 (45.5)
Arthritis 0.002
No 258 (91.2) 193 (74.8) 65 (25.2)
Yes 25 ( 8.8) 11 (44.0) 14 (56.0)
Physical activity b (Mets) 0.949#
Low 15 (5.7) 11 (73.3) 4 (26.7)
Moderate 135 (51.1) 95 (70.4) 40 (29.6)
High 114 (43.2) 83 (72.8) 31 (27.2)
Depressive symptoms c 0.004
No 264 (94.0) 195 (73.9) 69 (26.1)
Yes 17 (6.0) 7 (41.2) 10 (58.8)
a Chronic diseases included heart disease, arthritis, hypertension, diabetes mellitus, lung disease, peptic ulcers, liver disease, osteoporosis, gout, and cataracts. Heart disease and arthritis were significant, while the others were not. b mean±standard deviation: 4129.72±4811.94; c CES-D score:2.74±4.02. # Fisher’s exact test. Mets, metabolic equivalents.
Table 2 Distribution of quality of sleep
Variable items n %
Sleep duration (h)
0: ³7 197 69.6
1: 6~6.9 66 23.3
2: 5~5.9 15 5.3
3: £4.9 5 1.8
Sleep disturbance (scores)
0: 0 19 6.7
1: 1~9 246 86.9
2: 10~18 17 6.0
3: 19~27 1 0.4
Sleep latency (min)
0: £15 142 50.2
1: 16~30 65 23.0
2: 31~60 46 16.3
3: ³60 30 10.6
Daytime dysfunction
0: Very good 213 75.3
1: Fairly good 49 17.3
2: Fairly bad 19 6.7
3: Very bad 2 0.7
Sleep efficiency (%)
0: ³85 248 87.6
1: 75~84 23 8.1
2: 65~74 7 2.5
3: £64 5 1.8
Subjective sleep quality
0: Very good 32 11.3
1: Fairly good 162 57.2
2: Fairly bad 63 22.3
3: Very bad 26 9.2
Use of sleep medication
0: Not during past month 237 83.7
1: Less than once a week 10 3.5
2: Once or twice a week 7 2.5
3: Three or more times a week 29 10.2
Global sleep quality
Good quality (£5) 204 72.1
Poor quality (>5) 79 27.9
Table 3 Distribution of health-related fitness between good and poor sleep quality using the Mann-Whitney U-test (N=283)
Variables With good sleep quality (n=204) With poor sleep quality (n=79) z/p
Mean rank Sum of ranks Mean rank Sum of ranks
Basic condition
Age 143.77 29329.00 137.43 10857.00 -0.585/0.558
Depression 120.49 24338.00 193.46 15283.00 -7.190/0.000
Chronic disease numbers 135.97 27737.50 157.58 12448.50 -2.125/0.034
Self-rated health 157.17 31906.00 98.91 7715.00 -5.399/0.000
Anthropometric index
BMI (kg/m2) 145.34 29648.50 131.47 10254.50 -1.278/0.201
FFMI 144.65 28896.50 141.11 11006.50 -0.050/0.960
Mid-arm circumference (cm) 145.22 29625.00 131.77 10278.00 -1.239/0.215
Waist/hip ratio 142.12 28992.00 139.88 10911.00 -0.206/0.837
Physical fitness
Sit-and-reach (cm) 145.06 29447.00 130.44 10174.00 -1.351/0.177
One leg stance (s) 141.44 28711.00 139.87 10909.80 -1.860/0.853
Two-min step (no. of times) 146.35 29710.00 127.06 9911.00 -1.782/0.075
Chair stand in 30 s (no. of times) 145.77 29592.00 128.58 10029.00 -1.593/0.111
Grip muscle strength (kg) 145.51 29539.00 127.29 9801.00 -1.682/0.093
Up-and-go (s) 134.13 27229.00 158.87 12392.00 -2.324/0.020
Back muscle strength (kg) 143.68 28736.00 128.87 10045.00 1.388/0.165
BMI, body-mass index; FFMI, free fat mass index.
Table 4 Spearman correlation between the Pittsburgh Sleep Quality Index (PSQI) and health-related fitness
PSQI
r p
Basic condition
Age .004 0.952
Depression .491 0.000
Self-rate health -.391 0.000
Chronic disease (Numbers) 0.200 0.001
Anthropometric index
BMI -.076 0.204
FFMI .001 0.987
Waist / hip ratio .011 0.857
Physical Fitness
Sit-and reach -.131 0.028
One-leg stand -.080 0.179
Two-min steps -.133 0.026
Chair stand in 30s -.158 0.080
Grip muscle strength -.105 0.195
Up-and-go -.169 0.004
Back muscle strength -.100 0.096
Table 5A. Logistic regression analysis of poor sleep quality with the global score and with seven components of the Pittsburgh Sleep Quality Index (PSQI) (N=283)
Variable
|
Odds ratio
|
Poor sleep quality
|
Short sleep duration
|
Sleep disturbance
|
Longer sleep latency
|
Daytime dysfunction
|
Poor sleep efficiency
|
Poor subjective sleep quality
|
Use of sleep medication
|
Age
|
1.005
|
1.010
|
0.925*
|
0.974
|
1.010
|
1.008
|
0.986
|
1.036
|
Sex
|
1.529
|
4.753
|
3.910
|
0.836
|
1.027
|
2.465
|
1.238
|
0.737
|
Alcohol consumption
|
0.573
|
0.876
|
1.015
|
0.790
|
0.826
|
1.747
|
0.648
|
0.405
|
CES-D score
|
1.220***
|
1.172*
|
1.225***
|
1.096*
|
1.143*
|
1.003
|
1.260***
|
1.148**
|
Chronic disease numbers
|
0.524*
|
0.404
|
0.8722
|
0.604*
|
0.629
|
0.830
|
0.650*
|
0.962
|
Self-rated health
|
0.865***
|
0.948
|
0.972
|
0.885**
|
0.960
|
0.926
|
0.856***
|
0.869**
|
Arthritis
|
4.562**
|
4.180
|
5.815**
|
2.38
|
2.126
|
2.922
|
2.959
|
1.622
|
Heart disease
|
2.296
|
0.000
|
0.869
|
1.430
|
1.665
|
0.000
|
1.046
|
2.298
|
Sit-and-reach
|
0.991
|
0.956
|
0.962
|
0.994
|
0.980
|
0.985
|
1.004
|
0.994
|
Two-min step
|
1.000
|
0.984
|
0.981
|
0.985*
|
1.003
|
0.998
|
0.993
|
0.993
|
Up-and-go
|
1.109
|
1.130
|
1.384
|
1.044
|
1.109
|
1.063
|
1.098
|
0.994
|
Constant
|
0.548
|
0.071
|
0.950
|
40.344
|
0.024
|
0.060
|
5.251
|
0.246
|
Note: * p<0.05, ** p<0.01, *** p<0.001.
CES-D, Center for Epidemiological Studies Depression Scale.
Table 5B. Logistic regression analysis of poor sleep quality with the global score and with seven components of Pittsburgh Sleep Quality Index (PQSI) (N=283)
Variable
|
95% Confidence interval
|
Poor sleep quality
|
Short sleep duration
|
Sleep disturbance
|
Longer sleep latency
|
Daytime dysfunction
|
Poor sleep efficiency
|
Poor subjective sleep quality
|
Use of sleep medication
|
Age
|
(0.960, 1.052)
|
(0.936, 1.090)
|
(0.846, 1.011)
|
(0.931, 1.018)
|
(0.941, 1.083)
|
(0.937, 1.084)
|
(0.943, 1.032)
|
(0.979, 1.095)
|
Sex
|
(0.625, 3.742)
|
(0.494, 45.703)
|
(0.512, 29.751)
|
(0.383, 1.825)
|
(0.283, 3.725)
|
(0.487, 12.475)
|
(0.528, 2.902)
|
(0.283, 1.923)
|
Alcohol consumption
|
(0.234, 1.404)
|
(0.173, 4.427)
|
(0.193, 5.338)
|
(0.356, 1.751)
|
(0.212, 3.222)
|
(0.503, 6.072)
|
(0.281, 1.497)
|
(0.114, 1.435)
|
CES-D score
|
(1.116, 1.333)
|
(1.043, 1.318)
|
(1.091, 1.376)
|
(1.015, 1.183)
|
(1.034, 1.262)
|
(0.884, 1.137)
|
(1.145, 1.387)
|
(1.051, 1.235)
|
Chronic disease numbers
|
(0.789, 6.684)
|
(0.165, 0.986)
|
(0.389, 1.951)
|
(0.382, 0.954)
|
(0.306, 1.294)
|
(0.401, 1.719)
|
(0.403, 1.049)
|
(0.568, 1.630)
|
Self-rated health
|
(0.792, 0.944)
|
(0.822, 1.093)
|
(0.833, 1.135)
|
(0.815, 0.961)
|
(0.838, 1.100)
|
(0.808, 1.063)
|
(0.785, 0.934)
|
(0.784, 0.963)
|
Arthritis
|
(1.513, 13.753)
|
(0.503, 34.773)
|
(1.115, 30.324)
|
(0.701, 5.926)
|
(0.410, 11.408)
|
(0.556, 15.351)
|
(0.995, 8.798)
|
(0.994, 5.329)
|
Heart disease
|
(0.315, 0.873)
|
(0.000 )
|
(0.148, 5.087)
|
(0.511, 3.999)
|
(0.339, 8.183)
|
(0.000)
|
(0.358, 3.053)
|
(0.776, 6.808)
|
Sit-and-reach
|
(0.963, 1.020)
|
(0.914, 0.999)
|
(0.916, 1.011)
|
(0.967, 1.023)
|
(0.938, 1.024)
|
0.941, 1.031)
|
(0.975, 1.033)
|
(0.961, 1.028)
|
Two-min step
|
(0.986, 1.015)
|
(0.960, 1.009)
|
(0.954, 1.010)
|
(0.972, 0.999)
|
(0.980, 1.028)
|
(0.975, 1.021)
|
(0.979, 1.007)
|
(0.975, 1.011)
|
Up-and-go
|
(0.890,1.415)
|
(0.767, 1.666)
|
(0.902, 2.123)
|
(0.826, 1.319)
|
(0.761, 1.616)
|
(0.726, 1.554)
|
(0.865, 1.393)
|
(0.752, 1.315)
|